Chemical compositions adapted to interact with and modify the mechanical properties of fibers and fibrous structures have been described. Such compositions may be used to alter the appearance of a fibrous structure and/or change the mechanical properties of the fibers and the overall structure. The composition may be applied to the surface of the fibers/structures and subsequently activated by exposure to electromagnetic radiation of appropriate wavelength and intensity. This exposure activates the composition. Upon activation, the composition alters the mechanical properties of the fibers and structure via the altered fibers. This alteration may be achieved, at least in part, through covalent binding of an element within the composition to the fibers/structure being modified.
One form of said alteration is the retention of the fibers and structure of the form present at the time of activation. A straight fiber and flat structure may retain this shape after the exposure to the radiation and a wrinkled and/or otherwise curved or formed structure may retain its wrinkled and/or otherwise curved or formed state. What is desired is an apparatus adapted to concurrently impart a desired mechanical state to a structure and to appropriately irradiate the structure to activate a composition applied to the structure in anticipation of the use of the apparatus.